JPH04275098A - Pulse motor control circuit - Google Patents

Abstract

PURPOSE:To realize rotation of a pulse motor synchronized with an external synchronizing signal having frequency in slew region deviating from a self- starting region. CONSTITUTION:A pulse motor 1 is started in a self-starting region with accelerating/decelerating pulses outputted from a pulse generator 4. When the pulse motor 1 is accelerated upto an external synchronizing signal 6, a switching circuit 3 is switched by a signal fed from a sequencer 5 and the pulse motor 1 is rotated with the external synchronizing signal 6. Consequently, the pulse motor 1 can be rotated with the external synchronizing signal 6 in a slew region which deviates from the self-starting region.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pulse motor control circuit used to rotate a pulse motor in synchronization with an external synchronization signal in factory automation equipment, precision processing equipment, and the like.

0002

[Prior Art] Conventionally, in this type of pulse motor that rotates in synchronization with an external synchronization signal, the pulse motor is a synchronous motor that can obtain a rotation speed proportional to the pulse frequency. As shown in FIG. 5, an external synchronization signal 6 is directly input to the pulse motor driver 2 to rotate the pulse motor 1.

0003

However, the pulse motor has characteristics as shown in FIG. That is, if the pulse frequency is within the self-starting region, the pulse motor can be started in synchronization with this pulse frequency. However, as the frequency is increased, even if a pulse signal exceeding a certain frequency is input, the pulse motor loses synchronization and cannot be started. The frequency at this time is the maximum self-starting frequency, and the high speed region exceeding this is the through region. The pulse motor cannot be started with a pulse signal in this through range. However, the conventional pulse motor control circuit described above has a problem in that when the pulse frequency of the external synchronization signal is in the through range, step-out occurs and the pulse motor cannot be started.

The present invention solves these conventional problems and makes it possible to start and synchronously rotate a pulse motor even in response to an external synchronization signal with a pulse frequency in the through range beyond the self-start range. The purpose of this invention is to provide a pulse motor control circuit that can perform the following steps.

[0005]

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a pulse generator that generates acceleration/deceleration pulses whose frequency changes continuously, and an external synchronization signal that is input to the pulse motor driver. and a switching circuit for switching to the output signal of the pulse generator, and a sequencer for controlling the switching circuit and the pulse generator, and after starting the pulse motor within the self-starting region and accelerating it to near the external synchronizing signal, The rotation is synchronized with an external synchronization signal.

[0006]

[Operation] Therefore, according to the present invention, the pulse motor is started in the self-starting region by the pulse generator, and after the pulse motor is accelerated to the vicinity of the external synchronization signal, the switching circuit is switched by the control signal from the sequencer, and the pulse motor is By rotating the pulse motor using the synchronization signal, it is possible to obtain rotation of the pulse motor that is also synchronized with an external synchronization signal having a pulse frequency in the through range beyond the self-starting range.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows the structure of an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a pulse motor driven by a pulse motor driver 2. As shown in FIG. 3 is a switching circuit that selects the pulse signal input to the pulse motor driver 2, and has a circuit configuration as shown in FIG. 3(a), and as shown in FIG. 3(b), the switching signal S is When input A
is selected, and when the switching signal S is H, input B is selected. 4 is a pulse generator that generates an acceleration/deceleration pulse signal 10 whose frequency changes continuously. A sequencer 5 has a sequence control function and a counter function, and outputs a switching control signal 11 to the switching circuit 3 and an acceleration/deceleration pulse generation signal 12 to the pulse generator 4. Reference numeral 6 denotes an external synchronization signal input to the switching circuit 3 and the sequencer 5.

Next, the operation of the above embodiment will be explained. In the above embodiment, when starting the pulse motor 1, the sequencer 5 switches the input of the switching circuit 3 to the signal of the pulse generator 4 using the switching circuit control signal 11, and then sends the acceleration/deceleration pulse generation signal 12 to the pulse generator 4.
give. As a result, the pulse generator 4 generates acceleration pulses of increasing frequency continuously, as shown in A of FIG. 2, and the pulse signal 10 thereof is input to the pulse motor driver 2 through the switching circuit 3. Upon receiving the acceleration pulse, the pulse motor driver 2 drives the pulse motor 1, and the pulse motor 1 is started and accelerated as shown in FIG. 2B. Furthermore, at the point in time when the frequency of the output pulse of the pulse generator 4 becomes almost equal to the frequency of the external synchronization signal 6 (point S in FIG. 2), the sequencer 5 uses the switching circuit control signal 11 to change the input of the switching circuit 3 to the external synchronization signal. Switch to 6. At this time, in order to synchronize the output pulses of the pulse generator 4 and the pulses of the external synchronization signal 6, the external synchronization signal 6 is also input to the sequencer 5, and the acceleration time of the acceleration pulse of the pulse generator 4 (time T in FIG. 2)
The timing of the switching point (S point) is determined by managing the time using a counter function inside the sequencer 5. After switching, the pulse signal 13 input to the pulse motor driver 2 becomes the external synchronization signal 6, and the pulse motor 1 rotates in synchronization with the external synchronization signal 6, as shown in C of FIG.

As described above, according to the above embodiment, the input of the switching circuit 3 is switched by the sequencer 5 to the acceleration/deceleration pulse signal of the pulse generator 4, and the pulse motor 1 is started within the self-starting region. After accelerating to a frequency almost equal to the synchronization signal 6, the sequencer 5 switches the switching circuit 3.
Since the pulse motor 1 can be rotated by switching the input to the external synchronization signal 6, the pulse motor can also be rotated in synchronization with the external synchronization signal with a pulse frequency in the through range beyond the self-start range. It has the effect of being able to.

In the above embodiment, the pulse generator 4 generates acceleration pulses whose frequency continuously increases, but the pulse generator 4 generates deceleration pulses whose frequency continuously decreases. Therefore, the pulse motor 1, which is rotating at high speed in synchronization with the external synchronization signal 6, is decelerated and stopped by switching the external synchronization signal 6 to the deceleration pulse signal of the pulse generator 4. You can also do that.

Furthermore, in the above embodiment, the external synchronization signal 6 has a pulse frequency in the through region exceeding the self-starting region.
Although the pulse motor 1 is rotated in synchronization with the above, the external synchronization signal 6 may have a pulse frequency within the self-starting range. In this case, the acceleration/deceleration pulse signal of the pulse generator 4 is used to generate a shock-free smooth motor, compared to the case where the external synchronizing signal 6 is input directly to the pulse motor 1, or when the external synchronizing signal 6 is instantaneously stopped. - It has the effect of enabling quick start and stop.

0012

Effects of the Invention As is clear from the above embodiments, the present invention utilizes acceleration/deceleration pulse signals from a pulse generator to start and stop the pulse motor, and uses an external synchronization signal to operate the pulse motor synchronously. By switching these signals using a sequencer, throughput beyond the self-starting range can be achieved.
Synchronous operation of the pulse motor can also be realized with respect to external synchronization signals in the area.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a pulse motor control circuit in one embodiment of the present invention.

[Figure 2] Diagram explaining the operation of the circuit

[Figure 3] (a) Circuit diagram of the switching circuit of the same circuit (b) Truth table of the switching circuit of the same circuit

[Figure 4] Speed-torque characteristic diagram of pulse motor

[Figure 5] Block diagram of conventional pulse motor control circuit

[Explanation of symbols]

1 Pulse motor 2 Pulse motor driver 3 Switching circuit 4 Pulse generator 5 Sequencer 6 External synchronization signal

Claims (1)

[Claims] 1. A pulse motor driver that drives a pulse motor, a pulse generator that generates an acceleration/deceleration pulse signal whose frequency changes continuously, and a pulse signal input to the pulse motor driver that is connected to an external synchronization signal and the pulse generator. A pulse motor control circuit comprising a switching circuit for switching to an output signal of the pulse generator, and a sequencer for controlling the switching circuit and the pulse generator.